Pipe puller



W. F. HENRY PIPE PULL-ER Feb. 11,1958;

Filed April 11, 1955 2 Sheets-Sheet 1 INVENTOR. WILLIAM F. HENRY ATTORNEY Feb. 11, 1958 Filed April 11, 1955 W. F. HENRY PIPE FULLER 2 Sheets-Sheet 2 FIG. 5

INVENTOR.

WILLIAM F. HENRY ATTORNEY PIPE PULLER William F. Henry, Derby, Colo.

Application April 11, 1955, Serial No. 500,581

Claims. (Cl. 294-94) This invention relates to fishing tools for drill stems, pipes, and like tubular articles and more particularly to an improved and simplified device for pulling pipes from wells. This application is a continuation-in-part of my co-pending application, Serial No. 327,308, which was filed December 22, 1952, now abandoned, and entitled Pipe Puller.

In the drilling of wells, placing of casings, and in later pumping operations, sections of pipes and similar tubular articles sometimes become broken or otherwise detached beneath the surface of the earth. It is often difiicult with the devices presently commercially available to engage these loose pipe sections so that they may be withdrawn from the well, particularly if they are of small diameter.

It is the principal object of this invention, therefore, to provide an improved fishing device of simple construction for easily and eifectively pulling pipe from wells.

A further object of this invention is to provide an improved device which will readily grip the inner surfaces of a segment of pipe.

Other objects of the invention will appear as the description proceeds.

In the drawings:

Figure 1 is a front elevation of the improved pipe puller of this invention in a closed position for insertion into a pipe.

Figure 2 is a side elevation of the device of Figure 1.

Figure 3 is an end view from the bottom of the device of Figures 1 and 2.

Figure 4 is a side elevation of the improved pipe puller of this invention shown in an open position and seizing the inner walls of a section of pipe. In this adaptation of the invention, the spring clip 9 which will be described in more detail later is mounted at the base of the movable dog 2.

Figure 5 is a side elevation of another form of the improved pipe puller shown in open position and seizing the inner walls of a section of pipe. In this adaptation of the invention the spring clip 9 is mounted at the top (end nearest rod or pipe 3) of the movable dog.

Referring now specifically to the drawings there is here illustrated one embodiment of this invention. The pipe puller comprises essentially a pair of elongated gripping dogs or bars 1 and 2. The dogs are disposed in opposed relation and have loose slidable face to face contact. Dog 1 is fixed by welding or similar means to a section of rod or pipe 3 and dog 2 is movable with respect to dog 1. Each of the dogs has one toothed edge 4 bearing a plurality of upwardly inclined gripping teeth 5. Movable dog 2 is provided with a plurality of slanting slots 6 disposed one above the other along the length of the dog and all inclined in the same direction. As is apparent from the drawings, Figures 1, 2, 4 and 5, the ends of the slots in the movable dog which are the farthest removed from the rod or pipe 3 are the closest to the tooth edge of that dog. The slots in movable dog 2 are disposed generally downwardly and outwardly in the ice direction of teeth 5. The dogs are held in a slidable relationship by means of bolts 7 passing through a hole in fixed dog 1 and slot 6 in dog 2 and having nuts or heads 8. A semi-circular steel spring clip 9 is provided at the bottom end of movable dog 2 by means of bolt 10 attached to the end of the dog and nut 11. To prevent sticking, dogs 1 and 2 may, if desired, be separated by means of washers 13 or the like on bolts 7.

In operation the pipe puller is suspended from the end of a drill stem or cable or the like and dropped into the well and section of pipe to be removed. The puller initially is in a closed position in order to readily drop through a pipe or tube. This is facilitated by means of arcuate spring clip 9 wherein the length of the chord subtended by the arc is slightly greater than the diameter of pipe 12 thus serving to hold the dogs together on the downward trip. When the puller is well within that section of the pipe to be removed, its direction of movement is reversed. The length of the chord subtended by the arcuate spring clip 9 being of greater length than the diameter of the pipe first engages the inner walls or" the pipe causing the dogs to separate by sliding longitudinally, opening the puller and engaging the inner walls of the pipe with teeth 5. As resistance is offered to the lifting movement, the engagement of the teeth of the dogs will increase. Thus engaged, the pipe may readily be withdrawn from the well. Since it is the arcuate spring clip which causes the dogs to separate or to be held together rather than the force of gravity, the puller may be used successfully either in a horizontal, upward, or downward position.

The dimensions of the puller will, of course, be dependent upon the inside diameter of the pipe which is to be pulled. The following dimensions are illustrative. For a pipe of about 2 inches inside diameter a fixed dog 14% by 1 by inches was welded to a section of 1 inch pipe. The movable dog was 13 by 1% by /s inches. Two slots by 3 /2 inches in the movable dog at an angle of about 7 from the vertical slanting downwardly toward the toothed edge allowed expansion of the puller to about 2% inches. On one occasion, using a puller of these dimensions formed of mild steel strap, a ZOO-foot length of 2-inch pipe weighing 730 pounds and filled with water making a total weight of about 1,300 pounds was lifted from a 404-foot well with ease.

It is apparent that the construction of this device is such that it is adaptable for pulling pipes of any dimension and the construction of a puller of any particular size is within the skill of the art. As the diameter of pipe increases the weight increased progressively so that the length of the dogs should be increased accordingly. Thus, for a pipe of 6 inches in diameter or over, a length of 15 feet is suggested.

It is apparent that many modifications and variations of the invention as hereinbefore set forth may be made without departing from the spirit and scope thereof. The examples given are by way of illustration only, and the invention is limited only by the terms of the appended claims.

I claim:

1. A pipe puller comprising an elongated pulling member, a first elongated dog secured to one end of said elongated pulling member, a second movable elongated dog in face-to-face relationship to said first elongated dog, teeth in one longitudinal edge of said first dog, teeth in the opposite longitudinal edge of said movable dog, the face of the teeth in said dogs pointing toward said elongated pulling member, a plurality of slots in said movable dog wherein the ends of said slots the farthest removed from said pulling member are the closest to said tooth edge of said movable dog, fastening means extending through said slots to hold the dogs in slidable face-toface relationship and an arcuate spring clip rigidly fast tened to the terminal portion of said movable dog urging said pair of elongated dogs together when said pipe puller moves within a pipe in redirection which tends to reduce the radius of curvature .of said arcuatelspring clip and urging said pair of elongated dogs vapart when said pipe puller moves within a pipe .in a direction which tends to increase the radius of curvature of said arcuate spring clip.

2. A pipe puller comprising an elongated pulling member, a first elongated dog secured to .one .end of said elongated pulling member, a second movable elongated dog in face-to-face relationship to said first elongated dog, teeth in one longitudinal edge .of said .firstdqg, teeth in the opposite longitudinal edge .of said movable 'dog, the face of the teeth in said dogs pointing toward said elongated pulling member, a plurality of' slots in said movable dog wherein the ends of said slots ,the farthest removed from said pulling memberare .theLolosest .tosaid tooth edge of said movable dog, fastening means extending through said slots to hold the dogs in slidablefaoeto-face relationship and an ,arcuate spring clip rig-idly fastened to the terminal portion of .said'mosiable ,dog urging said pair of elongated dogs together when said pipe puller moves within a pipe in a direction Whichtends to reduce the radius of curvature of said arouate spring clip and urging said pair of elongated dogs apart when said pipe puller moves within a pipe in adi-rection which tends to increase the radius of curvature ofsaidarcuate spring clip, the length of the chord subtended by said arcuate spring clip being greater thanthe inside'diameter of the pipe to be pulled.

3. A pipe puller comprising an elongated pulling member, a first elongated dog secured to one end of said elongated pulling member, a second movable elongated dog in face-to-face relationship to said first elongated dog, teeth in one longitudinal edge of said first dog, teeth in the opposite longitudinal edge of said movable dog, the face of the teeth in said dogs pointing toward said elongated pulling member, a plurality of slots in said movable dog wherein the ends of said slots the farthest removed from said pulling member are the closest to said tooth edge of said movable dog, bolt fastening means extending through said slots to hold the dogs in slidable face-to-face relationship and an arcuate spring clip rigidly fastened to the terminal portion of said movable dog urging said pair of elongated dogs together when said pipe puller moves within a pipe in a direction which tends to reduce the radius of curvature of said'arcuate spring clip and urging said pair of elongated dogs apart when said pipe puller moves within a pipe in a direction which tends to increase the radius of curvature of said arcuate spring clip, the length of the chord subtended by said arcuate spring clip being greater than the inside diameter of the pipe to be pulled.

4. The pipe puller of claim 1 wherein the arcuate spring clip is rigidly fastened to the end of the movable dog toward which the face of the teeth point.

5. The pipe puller of claim 1 wherein the arcuate spring clip is rigidly fastened tothe end of the movable dog opposite the end toward which the teeth point.

No references cited. 

